Cleanest car in North America is the world's top-selling electric car

Among large automakers, Nissan has led the way into the electric car revolution. Its Nissan Leaf is available more widely than any other electric car, and it recently passed 100,000 global sales (the first to do so). It was also the top-selling electric car in the US in January, by far, after barely losing out to the Chevy Volt in 2013. Now, Nissan also has some big green bragging rights—the Automotive Science Group has named it the cleanest car in North America based on a comprehensive life-cycle assessment of over 1,300 automobiles.

The Automotive Science Group (ASG) is very proud of the ranking system it has developed, comparing itself to Google. It ranks cars in 9 categories, so it's not just evaluating their green cred. In each of the categories, it includes numerous factors in its analysis.

"ASG’s Automotive Performance Index is for automotive consumers what Google is for web users. Google presents the best of the web to users based on their data-driven page rank technologies. Likewise, ASG optimizes the automotive consumer search using proprietary algorithms and data-driven analysis to ensure the best vehicles are identified and differentiated in the highly competitive marketplace," the company notes.

"Consumers can now prioritize vehicle choices based on ethical and/or budgetary objectives. Whether it’s a commitment to buy American-made, an environmental prerogative to reduce one’s carbon footprint, or purely an economic choice to save thousands of dollars in fuel costs, ASG’s vehicle ratings are the guidepost for the 21st Century car buyer."

When it came to the green ranking, ASG only included cars with a minimum capacity of 4 passengers (the Leaf seats 5). The Nissan Leaf came out on top for many reasons, including its 114 MPGe "fuel economy" rating and the fact that it is assembled in the US. The best non-electric car in this category was the 40 MPG Mitsubishi Mirage, which helps to show how much more fuel efficient electric cars are. If you actually look at the list of the top 10 (or even top 15) most fuel-efficient cars in the US, they are all plug-in electrics. There's just no competing with them in this arena.

Outside of this overall ranking, several electric cars and the Leaf ranked in various other categories. In case you're not an electric car aficionado, I'm underlining the plug-ins below.